Integration Manual

LISA-U series - System Integration Manual
3G.G2-HW-10002-A3 Preliminary System description
Page 56 of 160
 Power saving configuration is active and the timeout from last data received to idle-mode start is set to 2000
frames (AT+UPSV=1,2000)
Figure 26 shows the case where DCE is in idle-mode and a wake-up is forced. In this scenario the only character
sent by the DTE is the wake-up character; as a consequence, the DCE will return to idle-mode when the timeout
from last data received expires. (2000 frames without data reception).
CTS OFF
CTS ON
Active mode is held for 2000 GSM frames (~9.2 s)
time
Wake up time: up to 15.6 ms
time
TxD
module
input
Wake up character
Not recognized by DCE
Figure 26: Wake-up via data reception without further communication
Figure 27 shows the case where in addition to the wake-up character further (valid) characters are sent. The
wake up character wakes-up the DCE. The other characters must be sent after the “wake up time” of 20 ms. If
this condition is satisfied, the characters are recognized by the DCE. The DCE is allowed to re-enter idle-mode
after 2000 GSM frames from the latest data reception.
CTS OFF
CTS ON
Active mode is held for 2000 GSM frames (~9.2s)
after the last data received
time
Wake up time: up to 15.6 ms
time
TxD
module
input
Wake up character
Not recognized by DCE
Valid characters
Recognized by DCE
Figure 27: Wake-up via data reception with further communication
LISA-U2 series modules don’t wake-up from idle-mode to active-mode via data reception by TxD input
line, if HW flow control is enabled.
The “wake-up via data reception” feature can’t be disabled.